Furniture Guided in a Synchronised Manner

ABSTRACT

A piece of furniture ( 10 ), in particular an item of office furniture or furniture for young persons, comprises body ( 14 ) from which a drawer ( 11  through  13 ) may be pulled out in a drawer motion direction ( 19 ) along a drawer path ( 27 ), such drawer running on a guide arrangement ( 20 ) on the body ( 14 ), and on two mutually opposite side portions ( 28  and  29 ), parallel to the drawer motion direction ( 19 ), of the drawer ( 11  through  13 ) gear wheels ( 30 ) synchronously coupled together are in mesh with racks ( 39 ) set on the body ( 14 ), for parallelization of the drawer ( 11  through  13 ) so that on the body the drawer does not run askew to the drawer motion direction ( 19 ). The racks ( 39 ) are constituted by tooth sections ( 32  and  33 ) on a front and/or a rear terminal section ( 25  and  26 ) of the drawer path ( 27 ). The gear wheels ( 30 ) are out of mesh with a rack ( 39 ) in a drawer path part clear of the tooth sections ( 32  and  33 ) in the front and/or the rear terminal section ( 25  and  26 ).

The invention relates to a piece of furniture and in particular office furniture or furniture for young persons, comprising a body from which a drawer may be pulled out in a drawer motion direction along a drawer path, such drawer being guided on a guide arrangement on the body, and two synchronously coupled gear wheels placed on two mutually opposite side portions, parallel to the drawer motion direction, of the drawer meshing with gear racks arranged on the body for parallel guidance of the drawer so that the drawer does not run skew and athwart the drawer motion direction on the body.

Furniture with so-called synchronous drawers is known. In the case of known furniture the mutually coupled gear wheels on the two sides mesh with gear racks, as for example toothed bars or the like, extending continuously from the rear to the front abutment in the path of motion of the drawer. Owing to the continuously synchronized rack engagement of the gear wheels it is possible to ensure that the drawer does not run askew and/or being buckled and the drawer can not for example be pushed back in.

The synchronized meshing of the gear wheels with the rack bars however does lead to greater frictional resistance. Pulling out the drawer from the body or pushing the drawer back in is accordingly hindered. This is however tolerated because the drawer is prevented from running skew by the synchronization.

Accordingly it is one aim of the present invention to so improve furniture with a drawer of the type initially mentioned that on the one hand skew running of the drawer is prevented and on the other hand mechanical resistance on pulling out the drawer from the body and moving it back into the body is reduced.

In order to attain this object in the case of piece of furniture of the type initially mentioned there is a provision such that the racks are constituted by tooth sections on a front and/or a rear terminal section of the drawer path and that the gear wheels in a drawer path part clear of the tooth sections are disengaged from a rack in the front and/or rear terminal section.

The piece of furniture in accordance with the invention is preferably office furniture, as for instance a cabinet or a desk. However the invention is in particular applicable to furniture for young persons or for children.

In the drawer path part in which the gear wheels are not in engagement with a rack, i. e. not in engagement with one of the tooth sections, the drawer is able to move freely, i. e. the gear wheels are stationary or are able to turn freely. The part of the drawer path in which the gear wheels are disengaged from the racks could also be named the “free section” of the drawer path. In this section there is, apart from the comparatively low friction in the guide arrangement, which for example will comprise telescoping bars, no frictional resistance to be overcome by a user of the furniture when moving the drawer. When the drawer is pulled and pushed in it runs quite freely into and out of the body. It is merely in the end sections of the drawer's path, as for example in the front and/or rear end sections, that the gear wheels are engaged for parallel guidance of the drawer with respective tooth sections and prevent skew running of the drawer. The drawer can accordingly be guided parallel to itself as far as its respective front or front terminal abutment into or out of the body.

In the development of the invention it has been found that the gear wheels, when they clear the free section of the drawer path and arrive at the terminal sections with the racks, more or less automatically synchronize themselves and align themselves longitudinally and transversely in relation to the drawer motion direction. Admittedly it is possible for the drawer to run somewhat askew or be buckled in the middle, free section between the tooth sections at the terminal portions of the drawer path. But when the gear wheels arrive at the tooth sections, they will right the drawer and true it up with the drawer motion direction correcting any possible skew positioning or buckling of the drawer.

The gear wheel firstly engaging a tooth section in the direction of motion of the drawer will be retarded, because it must overcome a greater resistance than the coupled gear wheel arranged at the opposite side of the drawer. When finally both gear wheels engage the tooth sections, i. e. when both gear wheels have run onto the tooth sections, the two gear wheels, which are synchronously coupled, will start to mesh with the teeth of the tooth sections and will thus true up the drawer so that the drawer is shifted on farther in the direction toward the respective abutments.

Admittedly it is a convenient measure to provide tooth sections, which are in accordance with the invention, both on the front and also on the rear end portion of the drawer path. However in principle it is possible for example to provide short tooth sections in accordance with the invention only at the front or the rear section of the drawer path.

The gear wheels are preferably arranged obliquely at the bottom in the rear portion of the drawer. In addition to this particularly space saving arrangement in the rear bottom corner portion of the drawer arrangements are also advantageous in which, dependent on the particular configuration, the gear wheels are arranged underneath the drawer or behind the drawer.

In accordance with an expedient measure in accordance with the invention the front tooth sections extend as far as a front terminal abutment delimiting the path of movement of the drawer. The same is also advantageous in the case of a rear terminal abutment. Accordingly the drawer is guided in parallelism and in a synchronized manner at the respective terminal section as far as the terminal abutment.

Between a tooth section at the terminal portion of the drawer path and a front and/or a rear terminal abutment in front of or, respectively, behind the tooth section it is also advantageous to have a clearance. This clearance is approximately so wide that the gear wheel meshing with the tooth section essentially fits between the at least one tooth section and the terminal abutment, when the drawer engages the latter. While the gear wheels are still in mesh with the tooth sections there is a higher degree of friction. When a gear wheel arrives in the free space between the tooth section and the terminal abutment, the frictional resistance and, respectively, the resistance to motion will decrease. The gear wheel will “snap” into the free clearance so that the drawer will automatically be drawn into the terminal position at the respective abutment.

In principle it will suffice if the gear wheels mesh with the tooth sections substantially without strain in order for there to be a synchronization and parallel guidance of the drawer. An advantageous measure is however such that the gear wheels mesh with a predetermined, increased strain with the tooth sections and accordingly the drawer is retarded in the respective terminal section of the drawer path. This means that the drawer dies not hit the terminal abutment but is more or less gently retarded at it before getting as far as the terminal abutment. A measure can be advantageous in accordance with which such strain increases from the section of the drawer path outside the tooth sections as far as a front or, respectively, rear terminal portion of the tooth sections toward the respective terminal abutment. The retarding action will increase along this path as far as the respective terminal abutment.

In accordance with a convenient feature of the invention the gear wheels are coupled with one another with the aid of a synchronizing shaft extending athwart the drawer motion direction. This synchronizing shaft may be retarded by a suitable friction bearing means and/or a brake arrangement so that the above mentioned retarding acting is attained or even improved on.

However in accordance with one possible design of the invention it is even possible to provide for coupling of the gear wheels by means of a transmission.

For instance a gear belt or a cable, more especially a cable provided with teeth, may be trained about the synchronous gear wheels coupled in rotation, more particularly guide pulleys connected in a torque transmitting manner, to synchronize since synchronization gear wheels meshing with the tooth sections.

The tooth sections are best arranged on a guide part, as for example a telescoping guide, of the guide arrangement. A tooth section may constitute an integral component of the guide part, on which it is for example molded or bonded.

However a modular design is also advantageous in the case of which the tooth sections are constituted by tooth element components. Such tooth element components may in the case of furniture in accordance with the invention be added later in order to achieve the desired synchronization or parallel guidance. The tooth element component is for example able to be arranged on the guide arrangement, f. i. able to be snapped into position, to be screwed on or the like. A particularly preferred measure is such that the tooth element component is f. i. able to be attached to the body of the furniture at a socket present on the body of the furniture, as for example holes arranged in a grid, or the like. For instance the tooth element component may comprise an angular component, on which a rack rail is arranged.

The drawer in accordance with the invention may be locked with the aid of a single locking means. The synchronization or, respectively, parallel guidance prevents the person using the furniture, for example owing to skew movement perpendicularly to the drawing direction, from causing disengagement from the locking means, for example a lock.

In the following some embodiments of the invention will be explained with reference to the drawings.

FIG. 1 a represents a diagrammatic side elevation of a first embodiment of a piece of furniture in accordance with the invention with one drawer stationary and in the case of which the drawer is pushed into a body of the piece of furniture.

FIG. 1 b shows the furniture in accordance with FIG. 1 a but with the drawer pulled out.

FIG. 2 a shows the drawer according to FIG. 1 a from above.

FIG. 2 b is a view from above of the drawer in accordance with FIG. 21 partly pushed just as far as at the point of engagement with a tooth section.

FIG. 3 shows the furniture in accordance with FIGS. 1 a through 1 b in a perspective elevation.

FIG. 4 is a detailed view of a guide arrangement in the furniture in accordance with FIG. 3 with a front and a rear tooth section, generally in accordance with a part A of FIG. 3.

FIG. 5 illustrates a second working example of furniture in accordance with the invention which only has tooth sections in the front terminal sections of its drawers.

FIG. 6 is a perspective view of part of the structure of FIG. 5, which shows a front tooth section generally corresponding to a section B in FIG. 5.

FIG. 7 shows a third working example of furniture in accordance with the invention with a drawer whose gear wheels are coupled with the aid of a cable or belt transmission.

FIG. 8 shows a modified design of the embodiment in accordance with FIGS. 2 a and 2 b in the case of which a clearance is left between front terminal tooth section and a front terminal abutment in the drawer path for the drawer's gear wheels.

A piece of furniture 10 is diagrammatically depicted in the FIGS. 1 a through 2 b and in FIG. 3 in perspective and in detail. Drawers 11, 12 and 13 are able to be pulled forward out of a body 14 having side walls, 15 and 16, a top wall 17 and a floor 18 in a drawer motion direction 19. In the FIGS. 1 a through 2 b the side walls 15 and 16 are only indicated in part and diagrammatically or in a sectioned manner.

The drawers 11 through 13 run on guide arrangements 20 on the body 14. The guide arrangements 20 include guide parts 21, as for example telescoping guides 21, which are secured to the side walls 15 and 16 and in which the drawers 11 through 13 run as well.

The piece of furniture 10 is able to be closed at the front by a roller shutter. As shown in FIG. 3 there is a shutter guide 22 on the floor 18 for a roller shutter 22 not illustrated to run on. The drawers 11 through 13 are for example sliding trays with an inner partition 23.

In comparison their depth in the drawer motion direction 19 the drawers 11 through 13 are comparatively wide. Accordingly drawers 11 through 13 tend to run askew on being drawn out of the body 14 and/or on being pushed into it. However a synchronization arrangement 24 steadies the drawers 11 through 13 at their front and rear terminal sections 25 and 26 of the paths 27 of the drawers 11 through 13 and so prevent skew running.

At two mutually opposite side portions 28 and 29 parallel to the drawer motion direction 19 gear wheels 30 are arranged coupled with a synchronizing shaft 31. The gear wheels 30 mesh with front and rear tooth sections 32 and 33 arranged on the side walls 15 and 16 in the portion with the front and rear terminal sections 25 and 26 of the drawer path 27. In a middle free section 34, lying between the terminal sections 25 and 26, the gear wheels 30 are out of engagement a rack, and in the present case with the tooth sections 32 and 33. The tooth sections 32 and 33 extend as far as a front and a rear terminal abutment 35 in the drawer path 27. The terminal abutments 35 and 36 are for example in the form of telescoping guides 21.

In the case of the diagrammatic showing in accordance with FIGS. 1 a through 2 b the shaft 21 runs underneath the drawer 11. However an arrangement of the shaft 31 or, respectively, of the gear wheels 30 is more particularly space saving in a rear corner portion of the drawer 11, as shown in FIG. 3.

The pulling out of the drawer 11 along the drawer path 27 takes place as follows:

Firstly the gear wheels 30 are engaged with the rear tooth sections 33. At the rear terminal section 25 the drawer 11 is accordingly synchronized and moves in parallelism to itself so that and runs free when it is pulled out. The drawer 11 enters the middle, free section 34 while guided and running completely parallel, that is to say it does not run askew. Normally the drawer 11 will move along the free section with this parallel alignment as related to the drawing direction.

Even if owing to a user clumsily grasping the drawer 11, for example owing to taking hold of it at the side at one of the side walls 15 or 16, so that in the section 34 the drawer runs askew in relation to the drawer motion direction 19, the synchronization arrangement 24 will resynchronize the drawer at the front terminal sections 25 again. The gear wheel 30 firstly engaging the associated front tooth section 32 will be retarded by this tooth section 32 until the second gear wheel 30 arranged on the opposite side engages or runs onto its associated front tooth section.

The two gear wheels 30 then engage the tooth sections 32 synchronously and mesh with such tooth sections 32 so that the drawer 11 arrives at the front terminal abutment 35 synchronized and guided for parallel movement.

Mutatis mutandis the same will apply in the opposite direction, that is to say on pushing the drawer 11 into the body 14.

The side walls 15 and 16 and/or the side walls of the drawers 11 through 13 may be comparatively thin and/or consist of a material which has little resistance to buckling. Nevertheless the drawers 11 through 13 are guided along the guide arrangements 20 synchronously and in parallelism to themselves, because the synchronization arrangement 24 prevents running askew.

The front and the rear tooth sections 32 and 33 are constituted by tooth element components 37. The tooth element components 37 comprise for example angular elements 38, as for instance bent pieces of sheet metal or plastic, with horizontally extending racks 39 which the gear wheels 30 may engage from above. The racks 39 are for example constituted by rack bar elements, which are set bonded, screwed or the like on a bottom limb 44′ projecting past the respective drawer 11, 12 and 13, of the angle pieces 38. The racks 39 may also be integral components of the angle pieces 38.

The tooth element components 37 many in principle be mounted using holes 40 arranged in a grid in the side walls 15 and 16, as for instance using screws, and/or snapped in place and/or bonded. Accordingly the tooth element components 37 may be fitted to existing furniture when such furniture 10 is later to be provided with a synchronizing system in accordance with the invention. Similarly like the tooth element components 37 the shaft 31 or, respectively, the gear wheels 30 may be fitted to existing drawers 11 through 13.

A further possible design in accordance with the invention may contemplate attachment of the angle piece 18 together with the guide rails 41 to the side walls 15 and 16. To take one example, the sheet metal angle pieces 38 can be gripped between the guide rails 41 and the respective side wall 15 and 16. It may be convenient to provide fitting holes inside the angle pieces 38 for attachment to the side wall 15, which for example are concentric with fitting holes 45 in the guide rail 41. One limb 44 in the angle piece 38 may f. i. extend upward, between the telescoping part 42 and the respective side wall 15 and 16 so that pins, not illustrated, which are for example inserted in holes 45 in the telescoping part 42, may also extend through the top limb 44 and accordingly attach the tooth element component 37 to the body 14.

In accordance with a further design the tooth element components 37 may be integrally joined to the telescoping guides 21. For instance the tooth element components 37 can be molded on the guide rails 41, which are arranged on the respective side wall 15 and 16, and will constitute integral components.

Using the guide rails 41 by means of ball or roller bearings (not illustrated) telescoping parts 42 are borne them in turn a telescoping part 43 is supported, for example by means of ball or roller bearings. The telescoping 43 are attached to the side walls of the drawers 11, 12 and 13.

In the case of a piece of furniture 50 (as shown in FIGS. 5 and 6) drawers 51 may be pulled out of a body 52 with outer side walls 53, a top wall 54 and a floor 55. The drawers 51 run on guide arrangements 58 arranged on inner side walls 56 and a middle side wall 57 in each case to the side adjacent to the drawers 51.

Between the inner side walls 56 and the associated outer side walls 53 there is an intermediate space in the working embodiment, for example to receive roller shutters. Guide rails 59 of the guide arrangements 58, which for example constitute components of telescoping guides 60, are arranged on the side walls 56 and 57 on the inside facing the drawers 51. The drawers 51 are secured to the telescoping guides 60 and able to be pulled out of the body 52 or, respectively, pushed into it.

Unlike the furniture 10 it is only at the front terminal sections 67 of the paths 69 of the drawers 51 that tooth sections 61 in accordance with the invention are arranged. At the rear terminal sections 68 of the drawer paths 69 there are no tooth sections in accordance with the invention. This is for example expedient since the drawers 51 are narrower than the drawers 11 through 13 so that there is less skew running. However at the end of the drawer, viz. in the front terminal sections 67, there will be synchronization and a parallel guiding action in accordance with the invention and furthermore a retardation of the drawers 51 owing to the front tooth sections 61.

The tooth sections 61 are for example rack tooth bars 63 arranged on the top side of projections 62, extending in the direction of the drawers 51, of the guide rails 59. The top racks of the rack tooth bars 63 are engaged by gear wheels 64 in the rear side portions of the drawers 51. The rack bars 63 are arranged on the top side of the projections 62 horizontally. The direction of their longitudinal extent corresponds to the drawer motion direction 19. In each case two gear wheels 64 arranged on opposite sides of the drawers 51 are coupled together by a shaft 65 in a torque transmitting manner so that the gear wheels 64 synchronously mesh with the tooth sections 61 on opposite sides of the drawers 51 and accordingly guide the drawers 51 in the front end section 64 of the drawer paths 69 in parallelism to the drawer motion direction 19.

Furthermore the gear wheels 64 retard the drawers 51 when meshing with the tooth sections 61.

In the reversed direction during pushing the drawers 51 inward the tooth sections 61, cooperating with the gear wheels 64, firstly get a synchronization and parallel guidance of the drawer 51. Once the drawers 51 are then on the move they may travel with little frictional resistance on farther on the next part of the drawer path 69 as far as the rear terminal section 68 or, respectively, rear terminal abutment, which is for example constituted by the telescoping guides 60. Thus the piece of furniture 50 may be readily operated.

A locking means 66, arranged for example on the middle side wall 57 to the rear, serves for locking the drawers 51. For instance, a lock, not visible in the drawing, is provided on the front side of the furniture 50 for operation of the locking means 66. Furthermore the locking means 66 preferably prevents more than one drawer from being pulled out of the body 52 at a time so that the furniture 50 does not topple over forward. The locking means 66 accordingly serves as a catch for the drawers.

The shafts 65 are arranged on the drawers 51 at the rear and project downward in front of the drawers 51 so that they do not require any space between the drawers 51 and a rear wall, not illustrated in FIG. 5, of the body 52

A particularly space saving design of a synchronizing or parallelizing guide arrangement is depicted in FIG. 7: in the case of a piece of furniture 70 one drawer 71 is able to be withdrawn from a body 80 with side walls 72. The drawer 71 runs on a guide arrangement, not illustrated in the figure. At one of the front or rear terminal sections 82 of the path 81 of the drawer 71 out of the body 80 tooth sections 73 are arranged internally on the side walls 72 to mesh with gear wheels 74 on the bottom side 78 of the drawer 71.

In contradistinction to the tooth section 32, 33 and 61 the tooth sections 73 are not horizontally but vertically orientated. The gear wheels 74 are accordingly placed with their flat side parallel to the bottom side 78 and able to turn on axles 79 on the drawer 71. The gear wheels 74 are coupled with each other by means of a transmission 75, in the present case in the form of a belt drive, for synchronous rotation. One toothed belt 76 runs about drive gear wheels 77 coupling them for synchronous rotation with each other. The gear wheels 77 are f. i. locked in rotation with the gear wheels 74 or are constituted by a second gear ring. The toothed belt 76 is crossed over for synchronization of the gear wheels 74 turning in opposite directions.

In accordance with a further design of the invention not illustrated the drawings gear wheels of the type 77 employed in the gear transmissions, have a toothed belt slung around them and are juxtaposed with the gear wheels 74 and mesh with them.

The above mentioned alternative design of the invention using synchronizing gear wheels 77 coupled by a transmission is an invention in its own right. In the case of this design of the invention continuous toothed bars could also be provided. For instance, the toothed bars would, unlike the tooth sections 73, extend right to the front essentially along the entire drawer path on the side walls 72.

In the case of a design 10′ of the furniture 10 in accordance with FIG. 8 the front tooth sections 33 are arranged spaced from the front terminal abutment 35. Between the tooth sections 32 and the front terminal abutment 35 there is a clearance D sufficient for a part of the outer periphery of the respective gear wheel 30 in mesh with the tooth section 32 to fit between the tooth sections 32 and the front terminal abutment 35. A corresponding clearance D is also present at the rear terminal abutment 36. 

1. A piece of furniture and in particular office furniture or furniture for young persons, comprising a body (14; 52 and 80) from which a drawer (11 through 13; 51 and 71) may be pulled out in a drawer motion direction (19) along a drawer path (27), such drawer being guided on a guide arrangement (20 and 58) on the body (14; 52 and 80) and two synchronously coupled gear wheels (30; 64 and 74) placed on two mutually opposite side portions (28 and 29) parallel to the drawer motion direction (19) of the drawer (11 through 13; 51 and 71) meshing with gear racks (39) arranged on the body (14; 52 and 80) for parallel guidance of the drawer so that the drawer (11 through 13; 51 and 71) does not run askew and athwart the drawer motion direction (19) on the body (14; 52 and 80), characterized in that the racks (39) are constituted by tooth sections (32, 33; 61 and 74) on a front and/or a rear terminal section (25, 26; 67 and 68) of the drawer path (27) and that the gear wheels (30; 64 and 74) in a drawer path part (34) clear of the tooth sections 32; 33′ 61 and 74) are disengaged from a rack (39) in the front and/or rear terminal section (25, 26; 67 and 68).
 2. The piece of furniture as set forth in claim 1, characterized in that the gear wheels (30; 64 and 74) are arranged in a rear portion of the drawer projecting downward or rearward or obliquely downward on the drawer (11 through 13; 51 and 71).
 3. The piece of furniture as set forth in claim 1 or in claim 2, characterized in that the front tooth sections (32, 33; 61 and 74) extend as far as a front terminal abutment (35) and/or the rear tooth sections (32, 33; 61 and 74) extend as far as a rear terminal abutment (36) on the drawer path.
 4. The piece of furniture as set forth in claim 1 or in claim 2, characterized in that between at least one tooth section (32, 33; 61 and 74)and a front or a rear terminal abutment (35 and 36) on the drawer path (27) in front of or to the rear of the at least one tooth section (32, 33; 61 and 74) there is a clearance (D) which is approximately so wide that at least a part of the outer periphery of the gear wheel meshing with the at least one tooth section (32, 33; 61 and 74) fits between the at least one tooth section (32, 33; 61 and 74) and the terminal abutment.
 5. The piece of furniture as set forth in any one preceding claim, characterized in that the gear wheels (30; 64 and 74) so mesh with a predetermined strain with the tooth sections (32, 33; 61 and 74) that the drawer is retarded in the respective terminal section (25, 26; 67 and 68) of the drawer path (27).
 6. The piece of furniture as set forth in claim 5, characterized in that the strain increases from the drawer path part (34) clear of the tooth sections (32, 33; 61 and 74) as far as a front or rear terminal portion of the tooth sections (32, 33; 61 and 74).
 7. The piece of furniture as set forth in any one of the preceding claims, characterized in that the gear wheels (30; 64 and 74) are coupled together by shaft (31 and 65) extending athwart the drawer motion direction (19).
 8. The piece of furniture as set forth in claim 7, characterized in that the shaft (31 and 65) is retarded by a friction bearing and/or a brake arrangement.
 9. The piece of furniture as set forth in any one of the claims 1 through 6, characterized in that the gear wheels (74) are coupled together by a transmission (75) and in particular a belt transmission.
 10. The piece of furniture as set forth in any one of the preceding claims, characterized in that the guide arrangement (20 and 58) has a guide part (21′), more especially a telescoping guide (21), on which at least one tooth section (32, 33; 61 and 74) is arranged.
 11. The piece of furniture as set forth in claim 10, characterized in that the at least one tooth section (32, 33; 61 and 74) constitutes an integral component of the guide part (21′).
 12. The piece of furniture as set forth in any one of the preceding claims, characterized in that the at least one tooth section (32, 33; 6 a and 74) is formed by a tooth element component (37), which is able to be attached on the guide arrangement (20 and 58) and/or in a socket, more particularly holes (40) arranged in grid, in the body (14; 52 and 80).
 13. The piece of furniture as set forth in any one of the preceding claims, characterized by a locking means (66) more particularly arranged on a side portion (28 and 29) of the drawer (11 through 13; 51 and 71) for locking the drawer (11 through 13; 51 and 71).
 14. The piece of furniture as set forth in any one of the preceding claims, characterized in that it is in the form of furniture for young persons and is more especially a wheel borne container or desk. 